Facile synthesis of graphitic carbon nitride/chitosan/Au nanocomposite: A catalyst for electrochemical hydrogen evolution.

This paper reports a novel nanocomposite catalyst comprised of graphitic carbon nitride (g-C3N4), chitosan and gold (Au) nanoparticles, which has been prepared through a facile, clean and low cost method. Graphitic carbon nitride has been fabricated by pyrolysis of urea. Laser ablation in liquid (LAL) was employed in the green synthesis of Au NPs. The g-C3N4/chitosan/Au nanocomposite (denoted as CN/CS/Au) were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), energy dispersive X-ray spectrometry (EDS), scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET) analyses. Chitosan biopolymer and a small amount of Au NPs were added to g-C3N4 to modify and improve the catalytic activity of g-C3N4. The activity of the hydrogen evolution reaction (HER) has been investigated using CN/CS/Au nanocomposite coated on a stainless steel mesh by electrochemical method. The amounts of hydrogen stored were calculated from cyclic voltammetry (CV) results. The results confirmed that chitosan and Au NPs were effective on the HER behavior of g-C3N4 and the nanocomposite had a good HER activity and stability.